Collected Evidence: Collected Evidence: Sow crops in spring rather than autumn A replicated, controlled, paired sites study from Sweden found more bird species on areas with spring sown cereals, compared with winter cereals. A before-and-after study from the UK found that several species bred in the study site for the first time after the start of spring sowing. Three studies from Sweden and the UK, two replicated and controlled, found population increases after the start of spring sowing, or higher populations on sites with spring-sown cereals, compared to sites with winter cereals. A before-and-after study from the UK found that ten species did not increase after spring sowing began. No species decreased. A replicated, controlled paired sites study from Sweden found that the benefits of spring-sowing decreased with the proportion of autumn-sown crops in the surrounding area. A replicated, controlled study from Sweden found that hatching success was lower on spring-sown crops than autumn sown.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F207https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F207Sun, 15 Jul 2012 17:16:58 +0100Collected Evidence: Collected Evidence: Soil: Grow cover crops in arable fieldsOrganic matter (12 studies): One meta-analysis of studies from Mediterranean-type climates and ten replicated, controlled studies (nine randomized, two before-and-after) from Italy, Spain, and the USA found more organic matter (mostly measured as carbon) in soils with winter cover crops, compared to soils without them, in some or all comparisons. One replicated, randomized, controlled, before-and-after study from Italy found inconsistent differences in organic matter in soils with or without winter cover crops (sometimes more, sometimes less). Nutrients (22 studies) Nitrogen (21 studies): Ten replicated, randomized, controlled studies (two before-and-after) from Italy, Spain, and the USA found more nitrogen in soils with winter cover crops, compared to soils without them, in some comparisons. One replicated, randomized, controlled study from the USA found less nitrogen in soils with winter cover crops, compared to soils without them. Ten replicated, controlled studies (nine randomized, two before-and-after) from Italy, Spain, and the USA found inconsistent differences in nitrogen (sometimes more, sometimes less) between soils with or without winter cover crops (but see the paragraphs, below, for distinctions between different forms of nitrogen). Phosphorus (1 study): One replicated, randomized, controlled study from the USA found similar amounts of phosphorus in soils with or without winter cover crops. Potassium (1 study): One replicated, randomized, controlled, before-and-after study from the USA found an increase in potassium in soils with winter cover crops, and no increase in soils without them. Soil organisms (12 studies) Microbial biomass (6 studies): Five replicated, randomized, controlled studies from the USA found more microbial biomass in soils with cover crops, compared to soils without them, in some or all comparisons. One replicated, randomized, controlled, before-and-after study from Italy found inconsistent differences in microbial biomass (sometimes more, sometimes less) between soils with or without winter cover crops. Nematodes (2 studies): Two replicated, randomized, controlled studies from the USA found more nematodes in soils with cover crops, compared to soils without them, in some comparisons. One of these studies also found a higher ratio of bacteria-feeding nematodes to fungus-feeding nematodes in soils with cover crops, compared to soils without them. Earthworms (2 studies): One replicated, controlled study from the USA found more earthworms in soils with winter cover crops, compared to soils without them. One replicated site comparison from the USA found similar numbers of earthworms in soils with or without winter cover crops. Bacteria and fungi (2 studies): One replicated, randomized, controlled study from Spain found more bacteria and fungi in soils with winter cover crops, compared to soils without them, in some comparisons. One replicated, controlled study from Italy found more spores and species of beneficial fungi (mycorrhizae) in soils with winter cover crops, compared to soils without them, in some comparisons. Soil erosion and aggregation (4 studies) Soil erosion (2 studies): Two controlled studies (one replicated and randomized) from Israel and the USA found less erosion of soils with cover crops, compared to soils with fallows or bare soils. Soil aggregation (2 studies): Two replicated, randomized, controlled studies from Spain and the USA found more water-stable soil aggregates in plots with winter cover crops, compared to plots without them, in some or all comparisons. Greenhouse gases (5 studies) Carbon dioxide (5 studies): Three controlled studies (two replicated and randomized) from Italy and the USA found similar amounts of carbon dioxide in soils with or without cover crops. Two replicated, randomized, controlled studies from the USA found more carbon dioxide in soils with cover crops, compared to soils without them, in some comparisons. Carbon storage (1 study): One replicated, randomized, controlled study from Italy found more carbon accumulation in soils with cover crops, compared to soils without them, in some comparisons. Nitrous oxide (2 studies): One replicated, randomized, controlled study from the USA found more nitrous oxide in soils with cover crops, compared to soils without them, in some comparisons. One controlled study from the USA found similar amounts of nitrous oxide in soils with cover crops or fallows. Implementation options (9 studies): Five studies from Italy, Spain, and the USA found more nitrogen in soils that were cover cropped with legumes, compared to non-legumes. One study from the USA found inconsistent differences in nitrogen (sometimes more, sometimes less) between soils with different cover crops. One study from the USA found no differences in phosphorus or microbial biomass between soils with different cover crops. One study from Italy found differences in beneficial fungi (mycorrhizae) between plots with different cover crops. One study from Spain found higher soil quality in plots with long-term cover crops, compared to short-term. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1345https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1345Wed, 08 Mar 2017 15:10:16 +0000Collected Evidence: Collected Evidence: Soil: Add compost to the soilOrganic matter (12 studies): Twelve replicated, controlled studies (ten randomized) from Italy, Spain, Syria, Turkey, and the USA found more organic matter in soils with added compost, compared to soils without added compost, in some or all comparisons. Nutrients (10 studies): Six replicated, controlled studies (five randomized) from Italy, Portugal, Spain, and Syria found more nutrients in soils with added compost, compared to soils without added compost, in some or all comparisons. Three replicated, randomized, controlled studies from Italy and the USA found inconsistent differences in nitrogen between soils with or without added compost. One replicated, randomized, controlled study from the USA found no differences in phosphorus between soils with or without added compost. Three replicated, randomized, controlled studies from Italy and Spain found similar pH levels in soils with or without added compost. Soil organisms (10 studies): Six replicated, controlled studies (five randomized) from Italy, Spain, and the USA found more microbial biomass in soils with added compost, compared to soils without added compost, in some or all comparisons. Two replicated, controlled studies from Italy and the USA found similar amounts of microbial biomass in soils with or without added compost. One replicated, randomized, controlled study from Italy found inconsistent differences in bacterial abundance between plots with or without added compost. Two replicated, randomized, controlled studies from Italy and Spain found differences in bacteria communities, in some comparisons. Soil erosion and aggregation (5 studies): Two replicated, controlled studies (one randomized) from Spain found less erosion of soils with added compost, compared to soils without added compost, in some or all comparisons. Four replicated, randomized, controlled studies from Spain and Turkey found that soils with added compost were more stable than soils without added compost, in some or all comparisons. Greenhouse gases (10 studies): Six replicated, controlled studies (five randomized) from Italy, Spain, and the USA found more greenhouse gas in soils with added compost, compared to soils without added compost, in some or all comparisons. Four replicated, randomized, controlled studies from Spain found no differences in greenhouse gas between soils with or without added compost. Implementation options (2 studies): One replicated, randomized, controlled study from Syria found more nitrogen in soils with compost added every two years, compared to soils with compost added every four years. One replicated, randomized, controlled study from Italy found inconsistent differences in bacteria abundance between soils with different amounts of added compost.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1362https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1362Mon, 08 May 2017 13:08:46 +0100Collected Evidence: Collected Evidence: Soil: Add manure to the soilOrganic matter (8 studies): Five replicated, controlled studies (two randomized) from Italy, Tunisia, Turkey, and the USA found more organic matter in soils with added manure, compared to soils without it. Three replicated, randomized, controlled studies from Italy, Spain, and Greece found similar amounts of organic matter in plots with or without added manure. Nutrients (5 studies) Nitrogen (5 studies): Three replicated, controlled, studies (one randomized) from Italy and Tunisia found more nitrogen in soils with added manure, compared to soils without it, in some comparisons. Two replicated, randomized, controlled studies from Greece and Italy found similar amounts of nitrogen in soils with or without added manure. Phosphorus (3 studies): One replicated, randomized, controlled study from Greece found more phosphorus in soils with added manure, compared to soils without it. One replicated, randomized, controlled study from Italy found similar amounts of phosphorus in soils with or without added manure. One replicated, controlled study from Italy found inconsistent differences in phosphorus between soils with or without added manure. Potassium (2 studies): Two replicated, randomized, controlled studies from Italy and Greece found more potassium in soils with added manure, compared to soils without it. pH (3 studies): One replicated, randomized, controlled study from Tunisia found lower pH levels in soils with added manure, compared to soils without it. One replicated, controlled study from Italy found higher pH levels in soils with added manure. One replicated, randomized, controlled study from Italy found similar pH level in soils with or without added manure. Soil organisms (3 studies) Microbial biomass (2 studies): Two replicated, randomized, controlled studies from Italy and Spain found similar amounts of microbial biomass in soils with or without added manure. Nematodes (1 study): One replicated, randomized, controlled study from Greece found similar numbers of nematodes in soils with or without added manure. Soil erosion and aggregation (4 studies): One replicated, randomized, controlled study from Spain found less erosion in plots with added manure, compared to plots without added manure. Three replicated, randomized, controlled studies from Spain and Turkey found higher soil stability in plots with added manure, compared to plots without added manure, in some or all comparisons. One replicated, controlled study from the USA found similar soil stability in plots with or without added manure. Greenhouse gases (2 studies): One replicated, controlled study from the USA found higher carbon dioxide emissions in plots with added manure, compared to plots without added manure. One replicated, randomized, controlled study from Spain found higher nitrous oxide emissions in plots with added manure, compared to plots without added manure. Implementation options (1 study): One study from Tunisia found no differences in organic matter or pH between soils with different amounts of added manure, but found less nitrate in soils with less added fertilizer.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1363https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1363Tue, 09 May 2017 10:32:58 +0100Collected Evidence: Collected Evidence: Soil: Add sewage sludge to the soilOrganic matter (1 study): One replicated, controlled study from the USA found more organic matter in soils with added sewage sludge, compared to soils without it. Nutrients (2 studies): One replicated, controlled study from Spain found more nitrate in soils with added sewage sludge, compared to soils without it. One replicated, randomized, controlled study from Portugal found similar amounts of nitrate in soils with or without added sewage sludge. Soil organisms (2 studies): Two replicated, controlled studies (one randomized) from Spain found similar amounts of microbial biomass in soils with or without added sewage sludge. Soil erosion and aggregation (2 studies): One replicated, controlled study from Spain found less erosion in plots with added sewage sludge, compared to plots without it. One replicated, controlled study from the USA found no difference in stability between soils with or without added sewage sludge. Greenhouse gases (2 studies): Two replicated, controlled studies from Spain and the USA found higher carbon dioxide emissions from soils with added sewage sludge, compared to soils without it. Implementation options (1 study): One replicated, controlled study from Spain found more nitrate in soils with digested sewage sludge, compared to composted or thermally dried sewage sludge.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1364https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1364Tue, 09 May 2017 14:12:57 +0100Collected Evidence: Collected Evidence: Soil: Add slurry to the soilOrganic matter (4 studies): Three studies (two replicated, randomized, controlled; one meta-analysis) from Spain and multiple Mediterranean countries found similar amounts of organic matter in soils with or without added slurry. One replicated, randomized, controlled study from Spain found more organic matter in soils with added slurry, compared to soils without it, in some comparisons. Nutrients (4 studies): Two replicated, randomized, controlled studies from Spain found more nitrate in soils with added slurry, compared to soils without it. Two replicated, randomized, controlled studies from Portugal and Spain found similar amounts of nitrate in soils with or without added slurry. One of these studies also found more ammonium, but another one did not. Soil organisms (2 studies): One replicated, randomized, controlled study from Spain found more microbial biomass in soils with added slurry, compared to soils without it, but another one did not. Soil erosion and aggregation (1 study): One replicated, randomized, controlled study from Spain found more stable soils in plots with added slurry, compared to plots without it, in some comparisons. Greenhouse gases (8 studies) Carbon dioxide (3 studies): Of three replicated, randomized, controlled studies from Spain, two studies found higher carbon dioxide emissions in soils with added slurry, compared to soils without it, but one study did not. Methane (4 studies): One replicated, randomized, controlled study from Spain found that less methane was absorbed by soils with added slurry, compared to soils without it. Three replicated, randomized, controlled studies from Spain found similar methane fluxes in soils with or without added slurry. Nitrous oxide (6 studies): Five replicated, randomized, controlled studies from Spain found higher nitrous oxide emissions in soils with added slurry, compared to soils without it, in some or all comparisons. One replicated, randomized, controlled study from Spain found similar nitrous oxide emissions in soils with or without added slurry. Implementation options (3 studies): One replicated, randomized, controlled study from Spain found no differences in organic matter or greenhouse-gas emissions between plots with different amounts of slurry. One replicated, randomized, controlled study from Spain found similar amounts of nitrogen in soils with or without added slurry. One replicated, randomized, controlled study from Spain found similar nitrous oxide emissions in soils with digested or untreated pig slurry. One replicated, randomized, controlled study from Spain found similar carbon dioxide and methane emissions in soils with digested or untreated slurry.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1365https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1365Tue, 09 May 2017 14:27:06 +0100Collected Evidence: Collected Evidence: Soil: Use organic fertilizer instead of inorganicOrganic matter (13 studies): Eight replicated studies (including one meta-analysis) from France, Italy, Spain, Turkey, and Mediterranean countries found more organic matter in soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Five replicated, randomized, controlled studies from Greece, Spain, and the USA found similar amounts of organic matter in soils with organic or inorganic fertilizer. Nutrients (14 studies) Nitrogen (9 studies): Four replicated studies (three controlled, two randomized; one site comparison) from France, Italy, and Spain found more nitrogen in soils with organic fertilizers, compared to inorganic fertilizer, in some comparisons. Five replicated, randomized, controlled studies from Greece, Spain, and the USA found similar amounts of nitrogen in soils with organic or inorganic fertilizer. Ammonium (3 studies): Two replicated, randomized, controlled studies from Italy and Spain found more ammonium in soils with organic fertilizer, compared inorganic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found similar amounts of ammonium in soils with organic or inorganic fertilizer. Nitrate (3 studies): One replicated, randomized, controlled study from Spain found less nitrate in soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Two replicated, randomized, controlled studies from Portugal and Spain found similar amounts of nitrate in soils with organic or inorganic fertilizer. Phosphorus (5 studies): Three replicated, randomized, controlled studies from Italy and Spain found more phosphorus in soils with organic fertilizer, compared to inorganic fertilizer, in some or all comparisons. One replicated site comparison from France found less phosphorous in soils with organic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found similar amounts of phosphorous in soils with organic or inorganic fertilizer. Potassium (6 studies): Three replicated, randomized, controlled studies from Italy and Spain found more potassium in soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Three replicated studies (two controlled, one site comparison) from France and Spain found similar amounts of potassium in soils with organic or inorganic fertilizer. pH (6 studies): Four replicated studies (three randomized and controlled, one site comparison) from France, Italy, and Spain found similar pH levels in soils with organic or inorganic fertilizer. One replicated, controlled study from Italy found higher pH levels in soils with organic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found lower pH levels in soils with organic fertilizer, in some comparisons. Soil organisms (7 studies) Microbial biomass (4 studies): Four replicated studies (three randomized and controlled, one site comparison) from France, Italy, and Spain found more microbial biomass in soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Other soil organisms (4 studies): One replicated, randomized, controlled study from Spain found fewer bacteria in soils with organic fertilizer, compared to inorganic fertilizer, in one comparison. One replicated site comparison from France found fewer nematodes in plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found fewer mites in plots with organic fertilizer, compared to inorganic fertilizer. One replicated, randomized, controlled study from Italy found inconsistent differences in microbes between plots with organic or inorganic fertilizer. Soil erosion and aggregation (5 studies): Three replicated, randomized, controlled studies from Turkey and Spain found greater aggregation in soils with organic fertilizer, compared to inorganic fertilizer, in some or all comparisons. Two replicated, randomized, controlled studies from Spain and the USA found no difference in aggregation between soils with organic or inorganic fertilizer. Greenhouse gases (11 studies) Carbon dioxide (5 studies): Four replicated, randomized, controlled studies from Italy and Spain found higher carbon dioxide emissions from plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons. One replicated, randomized, controlled study from Spain found similar carbon dioxide emissions from plots with organic or inorganic fertilizer. Methane (4 studies): Two replicated, randomized, controlled studies from Spain found that more methane was absorbed by soils with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Two replicated, randomized, controlled studies from Spain found that similar amounts of methane were absorbed by soils with organic or inorganic fertilizer. Nitrous oxide (8 studies): Five replicated, randomized, controlled studies from Spain found similar nitrous oxide emissions from plots with organic or inorganic fertilizer. Three studies (including one meta-analysis and two replicated, randomized, controlled studies) from Spain, the USA, and Mediterranean countries found lower nitrous oxide emissions from plots with organic fertilizer, compared to inorganic fertilizer, in some comparisons. Implementation options (4 studies): One study from Spain found that plots with slurry absorbed methane, but plots with manure emitted methane. One study from Italy found more organic matter, nutrients, and microbial biomass in plots fertilized with compost, compared to manure. One meta-analysis found lower nitrous oxide emissions after adding solid organic fertilizer, but not liquid organic fertilizer, compared to inorganic fertilizer. One study found inconsistent differences in soil bacteria with a single or double application of organic fertilizer.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1366https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1366Tue, 09 May 2017 15:33:46 +0100Collected Evidence: Collected Evidence: Soil: Plant or maintain ground cover in orchards or vineyardsOrganic matter (12 studies): Ten studies (eight replicated, randomized, and controlled, and two site comparisons) from Chile, France, Spain, and the USA found more organic matter in soils with ground cover, compared to soils without ground cover, in some or all comparisons. Two meta-analyses of studies from Mediterranean climates also found more organic matter in plots with ground cover. Implementation options (4 studies): One study from France found more organic matter in soils with permanent ground cover, compared to temporary ground cover, in one of three comparisons. Two studies from the USA found similar amounts of organic matter in soils with resident vegetation or seeded cover crops. One study from Spain found more organic matter where cover crops were incorporated into the soil. Nutrients (12 studies) Nitrogen (9 studies): Five studies (four replicated, randomized, and controlled, and one site comparison) from Chile and Spain found more nitrogen in soils with ground cover, compared to soils without ground cover, in some or all comparisons. One replicated, randomized, controlled study from the USA found less nitrogen in soils with ground cover, in some comparisons. Two replicated, randomized, controlled studies from Spain and the USA found inconsistent differences in nitrogen between soils with or without ground cover. One replicated site comparison from France found similar amounts of nitrogen in soils with or without ground cover. Implementation options (5 studies): Two studies from Spain and the USA found more nitrogen in soils that were cover cropped with legumes, compared to non-legumes, in some or all comparisons. Two studies from vineyards in the USA found similar amounts of nitrogen in soils with resident vegetation or seeded cover crops. One of these studies also found similar amounts of nitrogen in soils with different types of seeded cover crops, and in soils with or without tillage (both with ground cover). One study from Spain found more nitrogen where cover crops were incorporated into the soil. Phosphorus (4 studies): One replicated site comparison from France found more phosphorus in soils with ground cover, compared to bare soils, in one of six comparisons. Two studies (one replicated, randomized, and controlled, and one site comparison) from Spain and the USA found less phosphorus in soils with seeded cover crops, compared to tilled soils, in some comparisons. One replicated, randomized, controlled study from Chile found similar amounts of phosphorus in soils with seeded cover crops and bare soils. Implementation options (3 studies): One study from France found more phosphorus in soils with permanent ground cover, compared to temporary ground cover, in one of three comparisons. One study from the USA found similar amounts of phosphorus in soils with resident vegetation or seeded cover crops. One study from Spain found different amounts of phosphorus in soils with different types of seeded cover crops. Potassium (3 studies): One replicated, randomized, controlled study from Chile found more potassium in soils with seeded cover crops, compared to bare soils. Two site comparisons (one replicated) from France and Spain found similar amounts of potassium in soils with ground cover, compared to tilled or bare soil. Implementation options (1 study): One study from the USA found similar amounts of potassium in soils with resident vegetation or seeded cover crops. pH (4 studies): Two studies (one replicated, randomized, and controlled, and one site comparison) from Spain and the USA found lower pH levels in soils with ground cover, compared to soils without ground cover. One replicated, randomized, controlled study from Chile found higher pH levels in soils with ground cover. One replicated site comparison from France found similar pH levels in soils with or without ground cover. Soil organisms (6 studies) Microbial biomass (4 studies): Four replicated studies (three randomized and controlled, one site comparison) from France and the USA found more microbial biomass in soils with ground cover, compared to bare or tilled soils, in some or all comparisons. Implementation options (1 study): One study from France found more microbial biomass in soils with permanent ground cover, compared to temporary ground cover, in some comparisons. Fungi (2 studies): One replicated, controlled study from the USA found more symbiotic fungi (mycorrhizae) in soils with seeded cover crops, compared to tilled soils, in some comparisons, but found similar numbers of roots that were colonized by mycorrhizae. One replicated, randomized, controlled study from the USA found inconsistent differences in mycorrhizae in soils with seeded cover crops or tilled soils. Bacteria (1 study): One replicated, randomized, controlled study from Spain found more bacteria, but similar levels of bacterial diversity, in soils with ground cover, compared to bare soils. Nematodes (1 study): One replicated site comparison from France found more nematodes in soils with ground cover, compared to bare soils. Implementation options (1 study): One study from France found more nematodes in soils with permanent ground cover, compared to temporary ground cover, in one of three comparisons. Soil erosion and aggregation (10 studies) Soil erosion (7 studies): Six replicated, randomized, controlled studies from Chile, Italy, Spain, and the USA found less erosion of soils with ground cover, compared to bare or tilled soils, in some comparisons or all comparisons. One replicated, controlled study from France found similar amounts of erosion in plots with or without ground cover. Implementation options (1 study): One study from Italy found the least erosion with permanent cover crops, and the most erosion with temporary cover crops. Soil aggregation (5 studies): Four replicated, randomized, controlled studies from Chile and Spain found that soil aggregates were more water-stable in plots with seeded cover crops, compared to tilled or bare soils, in some or all comparisons. One site comparison from Spain found inconsistent differences in water stability between soils with seeded cover crops and bare soils. Greenhouse gases (3 studies): Two replicated, randomized, controlled studies from a vineyard in the USA found more carbon dioxide or nitrous oxide in soils with cover crops, compared to tilled soils. One replicated, randomized, controlled study from an olive orchard in Spain found similar amounts of carbon dioxide in soils with cover crops, compared to tilled soils. Implementation options (1 study): One study from the USA found similar amounts of carbon dioxide in soils with different types of ground cover.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1367https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1367Mon, 15 May 2017 14:10:27 +0100Collected Evidence: Collected Evidence: Soil: Use crop rotationsOrganic matter (9 studies): Five replicated, controlled studies (two randomized) from Italy, Portugal, and Spain found less organic matter in soils with crop rotations, compared to continuous crops, in some comparisons. One replicated, controlled study from Syria found more organic matter in soils with crop rotations, compared to continuous crops, in some comparisons. Three replicated, controlled studies from Spain found similar amounts of organic matter in soils with or without crop rotations. Nutrients (5 studies) Nitrogen (5 studies): One replicated, randomized, controlled study from Australia found more nitrogen in soils with crop rotations, compared to continuous crops, in one of four comparisons. One replicated, controlled study from Italy found less nitrogen in soils with crop rotations, compared to continuous crops, in some comparisons. One replicated, randomized, controlled study from Spain found inconsistent differences in nitrogen in soils with or without crop rotations. Two replicated, randomized, controlled studies from Portugal and Spain found similar amounts of nitrogen in soils with or without crop rotations. Phosphorus (2 studies): Two replicated, randomized, controlled studies from Portugal and Spain found less phosphorus in soils with crop rotations, compared to continuous crops, in some comparisons. pH (2 studies): Two replicated, randomized, controlled studies from Portugal and Spain found similar pH levels in soils with or without crop rotations. Soil organisms (3 studies) Microbial biomass (2 studies): One replicated, controlled study from Italy found more microbial biomass in soils with crop rotations, compared to continuous crops, in some comparisons. One replicated, randomized, controlled study from Spain found less microbial biomass in soils with crop rotations, compared to continuous crops, in some comparisons. Bacteria and fungi (1 study): One replicated, randomized, controlled study from Portugal found more fungi, but similar amounts of bacteria, in soils with crop rotations, compared to continuous crops. Soil erosion and aggregation (4 studies): One replicated, controlled study from Syria found higher water-stability in soils with crop rotations, compared to continuous crops. One replicated, randomized, controlled study from Spain found lower water-stability in soils with crop rotations, compared to continuous crops, in some comparisons. One replicated, randomized, controlled study from Spain found inconsistent differences in water-stability in soils with or without crop rotations. One replicated, randomized, controlled study from Spain found no differences in water-stability. Greenhouse gases (4 studies): One replicated, controlled study from Italy found higher carbon dioxide emissions from soils with crop rotations, compared to continuous crops, in some comparisons. One replicated, randomized, controlled study from Spain found similar carbon dioxide emissions from soils with or without crop rotations. One replicated, randomized, controlled study from Australia found lower nitrous oxide and methane emissions from soils with crop rotations, compared to continuous crops, but another one found no differences in nitrous oxide emissions. Implementation options (2 studies): Two studies from Syria and the USA found similar amounts of nitrogen in soils with two-year or four-year rotations. One of these studies also found similar amounts of organic matter.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1368https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1368Mon, 15 May 2017 14:21:47 +0100Collected Evidence: Collected Evidence: Soil: Use no tillage in arable fieldsOrganic matter (20 studies): One meta-analysis of studies from Mediterranean countries found more organic matter in soils without tillage, compared to soils with tillage. Fourteen replicated studies (eleven randomized and controlled, one controlled, one site comparison) from Italy, Spain, and the USA found more organic matter in soils without tillage, compared to soils with tillage, in some or all comparisons. One replicated, randomized, controlled study from Portugal found less organic matter in soils without tillage, compared to soils with tillage, in some comparisons. One replicated, randomized, controlled study from Spain sometimes found more organic matter, and sometimes found less, in soils without tillage, compared to soils with tillage. Three replicated, controlled studies (two randomized) from Italy and Spain found similar amounts of organic matter in soils with or without tillage. Nutrients (19 studies) Nitrogen (18 studies): Six replicated studies (five randomized and controlled, one site comparison) from Italy, Spain, and the USA found more nitrogen in soils without tillage, compared soil with tillage, in some or all comparisons. Six replicated, randomized, controlled studies from Spain found less nitrogen in soils without tillage, in some or all comparisons. Two replicated, controlled studies from Spain and the USA sometimes found more nitrogen and sometimes found less nitrogen in soils without tillage, compared to soils with tillage. Four replicated, controlled studies (three randomized) from Italy, Portugal, Spain, and the USA found similar amounts of nitrogen in soils with or without tillage. Phosphorus (5 studies): Three replicated, randomized, controlled studies from Spain and the USA found more phosphorus in soils without tillage, compared to soils with tillage, in some or all comparisons. One replicated, randomized, controlled study from Portugal found less phosphorus in soils without tillage, compared to soils with tillage, in some comparisons. One replicated, randomized, controlled study from Spain found similar amounts of phosphorus in soils with or without tillage. Potassium (3 studies): One replicated, randomized, controlled study from Spain found more potassium in soils without tillage, compared to soils with tillage, in some comparisons. One replicated, randomized, controlled study from the USA sometimes found more potassium and sometimes found less potassium in soils without tillage, compared to soils with tillage. One replicated, randomized, controlled study from Spain found similar amounts of potassium in soils with or without tillage. pH (2 studies): One replicated, randomized, controlled study from Portugal found lower pH levels in soils without tillage, compared to soils with tillage, in some comparisons. One replicated, randomized, controlled study from the USA found similar pH levels in soils with or without tillage. Soil organisms (18 studies) Microbial biomass (13 studies): Five replicated, controlled studies (four randomized) from Italy and Spain found more microbial biomass in soils without tillage, compared to soils with tillage, in some or all comparisons. Two replicated, randomized, controlled studies from Spain sometimes found more microbial biomass, and sometimes found less, in soils without tillage, compared to soils with tillage. Six replicated, randomized, controlled studies from Spain and the USA found similar amounts of microbial biomass in soils with or without tillage. Earthworms (2 studies): Two replicated studies (one controlled, one site comparison) from the USA found more earthworms in soils without tillage, compared to soils with tillage. Nematodes (2 studies): Two replicated, controlled studies (one randomized) from the USA found similar numbers of nematodes in soils with or without tillage. However, one of these studies found different communities of nematodes in soils with or without tillage. Mites (1 study): One replicated, controlled study from the USA found different communities of mites, but similar numbers of mites, in soils with or without tillage. Other soil organisms (1 study): One replicated, randomized, controlled study from Spain found similar amounts of denitrifying bacteria in soils with or without tillage. Another replicated, randomized, controlled study from Spain found more microorganisms in soils without tillage, compared to soils with tillage, in some comparisons. One replicated, randomized, controlled study from Portugal found more fungus in soils without tillage, compared to soils with tillage. Soil erosion and aggregation (9 studies): Seven replicated studies (six randomized and controlled, one site comparison) from Spain and the USA found that soils without tillage were more stable than tilled soils, in some or all comparisons. Two replicated, randomized, controlled studies from Spain found that soils without tillage were sometimes more stable, and were sometimes less stable, than tilled soils. Greenhouse gases (10 studies) Carbon dioxide (7 studies): Three replicated, controlled studies (two randomized) from Italy and Spain found more carbon dioxide in soils without tillage, compared to soils with tillage. Two replicated, randomized, controlled studies from Spain found less carbon dioxide in soils without tillage, compared to soils with tillage, in some comparisons. Two replicated, randomized, controlled studies from Spain sometimes found more carbon dioxide, and sometimes found less, in soils without tillage, compared to soils with tillage. One replicated, randomized, controlled study from Spain found similar amounts of carbon dioxide in soils with or without tillage. Nitrous oxide (3 studies): One replicated, randomized, controlled study from Spain sometimes found more nitrous oxide, and sometimes found less, in soils without tillage, compared to soils with tillage. Two replicated, randomized, controlled studies from Spain found similar amounts of nitrous oxide in soils with or without tillage. Methane (3 studies): One replicated, randomized, controlled study from Spain found less methane in soils without tillage, compared to soils with tillage. One replicated, randomized, controlled study from Spain sometimes found more methane, and sometimes found less, in soils without tillage, compared to soils with tillage. One replicated, randomized, controlled study from Spain found similar amounts of methane in soils with or without tillage. Implementation options (1 study): One replicated, randomized, controlled study from Spain found more organic matter in soils that had not been tilled for a long time, compared to a short time, in one comparison. This study also found greater stability in soils that had not been tilled for a long time, in some comparisons.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1369https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1369Mon, 15 May 2017 14:26:17 +0100Collected Evidence: Collected Evidence: Soil: Use no tillage instead of reduced tillageOrganic matter (6 studies): Three replicated, randomized, controlled studies from Spain found more organic matter in soils with no tillage, compared to reduced tillage, in some or all comparisons. Three replicated, randomized, controlled studies from Spain found similar amounts of organic matter in soils with no tillage, compared to reduced tillage. No studies found less organic matter in soils with no tillage, compared to reduced tillage. Nutrients (7 studies) Nitrogen (6 studies): Three replicated, randomized, controlled studies from Italy and Spain found more nitrogen in soils with no tillage, compared to reduced tillage, in some comparisons. Two of these studies also found less nitrogen in some comparisons. One replicated, randomized, controlled study from Spain found less nitrogen in soils with no tillage, compared to reduced tillage, in some comparisons. Two replicated, randomized, controlled studies from Spain found similar amounts of nitrogen in soils with no tillage, compared to reduced tillage. Phosphorus (2 studies): One replicated, randomized, controlled study from Spain found more phosphorus in soils with no tillage, compared to reduced tillage. One replicated, randomized, controlled study from Spain found similar amounts of phosphorus in soils with no tillage or reduced tillage. No studies found less phosphorus in soils with no tillage, compared to reduced tillage. Potassium (1 study): One replicated, randomized, controlled study from Spain found similar amounts of potassium in soils with no tillage or reduced tillage. No studies found less potassium in soils with no tillage, compared to reduced tillage. Soil organisms (8 studies) Microbial biomass (6 studies): Five replicated, randomized, controlled studies from Spain found similar amounts of microbial biomass in soils with no tillage or reduced tillage. One replicated, randomized, controlled study from Spain found more microbial biomass in soils with no tillage, compared to reduced tillage, in some comparisons, but found less in some comparisons. Bacteria (1 study): One replicated, randomized, controlled study from Spain found fewer denitrifying bacteria in soils with no tillage, compared to reduced tillage. Other soil organisms (2 studies): One replicated, controlled study from the USA found similar numbers of mites and nematodes, but different communities of mites and nematodes, in soils with no tillage, compared to reduced tillage. One replicated, randomized, controlled study from Spain found more mites in soils with no tillage, compared to reduced tillage. Soil erosion and aggregation (4 studies): One replicated, randomized, controlled study from Spain found more large aggregates in soils with no tillage, compared to reduced tillage, in some comparisons. One replicated, randomized, controlled study from Italy found similar aggregates in soils with no tillage or reduced tillage. One replicated, randomized, controlled study from Spain found higher water-stability in soils with no tillage, compared to reduced tillage, in some comparisons, but found lower water-stability in some comparisons. One replicated, randomized, controlled study from Spain found similar water-stability in soils with no tillage or reduced tillage. Greenhouse gases (4 studies): Two replicated, randomized, controlled studies from Spain found less greenhouse gas in soils with no tillage, compared to reduced tillage, in some comparisons. Two replicated, randomized, controlled studies from Australia and Spain found similar amounts of greenhouse gas in soils with no tillage or reduced tillage.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1370https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1370Mon, 15 May 2017 14:40:52 +0100Collected Evidence: Collected Evidence: Soil: Use reduced tillage in arable fieldsOrganic matter (14 studies): One meta-analysis from multiple Mediterranean countries found more organic matter in soils with reduced tillage, compared to conventional tillage. Eleven replicated studies (ten randomized and controlled, one site comparison) from Italy, Spain, Syria, and the USA found more organic matter in soils with reduced tillage, compared to conventional tillage, in some or all comparisons. Two replicated, randomized, controlled studies from Spain and the USA found similar amounts of organic matter in soils with reduced tillage or conventional tillage, in all comparisons. No studies found less organic matter in soils with reduced tillage, compared to conventional tillage. Nutrients (15 studies) Nitrogen (14 studies): Seven replicated studies (five randomized and controlled, one site comparison) from Italy, Spain, and the USA found more nitrogen in soils with reduced tillage, compared to conventional tillage, in some comparisons. Three of these studies also found less nitrogen in some comparisons. Two replicated, randomized, controlled studies from Spain found less nitrogen in soils with reduced tillage, compared to conventional tillage, in some or all comparisons. Five replicated, randomized, controlled studies from Spain, Syria, and the USA found similar amounts of nitrogen in soils with reduced tillage or conventional tillage, in all comparisons. Phosphorus (6 studies): Five replicated, randomized, controlled studies from Italy, Spain, and the USA found more phosphorus in soils with reduced tillage, compared to conventional tillage, in some or all comparisons. One replicated, randomized, controlled study from Spain found similar amounts of phosphorus in soils with reduced tillage, compared to conventional tillage, in all comparisons. Potassium (3 studies): Two replicated, randomized, controlled studies from Spain found more potassium in soils with reduced tillage, compared to conventional tillage, in some comparisons. One replicated, randomized, controlled study from Spain found similar amounts of potassium in soils with reduced tillage, compared to conventional tillage, in all comparisons. pH (1 study): One replicated, randomized, controlled study from Spain found similar pH levels in soils with reduced tillage or conventional tillage. Soil organisms (16 studies) Microbial biomass (15 studies): Eleven replicated, randomized, controlled studies from Italy, Spain, and the USA found more microbial biomass in soils with reduced tillage, compared to conventional tillage, in some comparisons. Two replicated, randomized, controlled studies from Spain and Syria found less microbial biomass in soils with reduced tillage, compared to conventional tillage, in some comparisons. Two replicated, randomized, controlled studies from Spain found similar amounts of microbial biomass in soils with reduced tillage or conventional tillage, in all comparisons. Bacteria (1 study): One replicated, randomized, controlled study from Spain found more denitrifying bacteria in soils with reduced tillage, compared to conventional tillage. Other soil organisms (2 studies): One replicated, controlled study from the USA found similar numbers of mites and nematodes, but differences in mite and nematode communities, in soils with reduced tillage, compared to conventional tillage. One replicated site comparison from the USA found more earthworms in fields with fewer passes of the plough, in one of three comparisons. Soil erosion and aggregation (9 studies) Soil aggregation (8 studies): Three replicated, randomized, controlled studies from Spain found that soil aggregates had higher water-stability in plots with reduced tillage, compared to conventional tillage, in some comparisons. One of these studies also found that soil aggregates had lower water-stability in some comparisons. One replicated, randomized, controlled study from Spain found that water-stability was similar in plots with reduced tillage or conventional tillage. One replicated, randomized, controlled study from Spain found more large aggregates in soils with reduced tillage, compared to conventional tillage, in one of two comparisons. One replicated, randomized, controlled study from Spain found smaller aggregates in soils with reduced tillage, compared to conventional tillage. Three replicated, randomized, controlled studies from Spain and the USA found similar amounts of aggregation in soils with reduced tillage or conventional tillage. Soil erosion (1 study): One replicated, randomized, controlled study from Egypt found less erosion with less tillage (one pass with the tractor, compared to two), but found more erosion with shallower tillage, compared to deeper. Greenhouse gases (11 studies) Carbon dioxide (9 studies): Three replicated, randomized, controlled studies from Spain found more carbon dioxide in soils with reduced tillage, compared to conventional tillage, in some or all comparisons. Three replicated, randomized, controlled studies from Spain and the USA found less carbon dioxide in soils with reduced tillage, compared to conventional tillage, in some or all comparisons. Three controlled studies from Italy, Spain, and the USA found similar amounts of carbon dioxide in soils with reduced tillage or conventional tillage, in all comparisons. Nitrous oxide (3 studies): Two replicated, randomized, controlled studies from Spain and the USA found more nitrous oxide in soils with reduced tillage, compared to conventional tillage, in some or all comparisons. One controlled study from the USA found similar amounts of nitrous oxide in soils with reduced tillage or conventional tillage, in all comparisons. Methane (1 study): One replicated, randomized, controlled study from Spain found similar amounts of methane in soils with reduced tillage or conventional tillage. Implementation options (1 study): One replicated, randomized, controlled study from Egypt found that less soil was lost in runoff water from plots that were tilled at slower tractor speeds. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1371https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1371Mon, 15 May 2017 14:50:31 +0100Collected Evidence: Collected Evidence: Soil: Plant buffer stripsOrganic matter (1 study): One replicated, randomized, controlled study from Italy found more organic matter in plots with buffers. Nutrients (1 study): One replicated, randomized, controlled study from Italy found more nitrogen in plots with buffers. Soil organisms (1 study): One replicated, randomized, controlled study from Italy found more microbial biomass in plots with buffers. Soil erosion and aggregation (0 studies) Greenhouse gases (0 studies) Implementation options (1 study): One study from Italy found some differences between buffers of different widths, and other differences between buffers with different numbers of trees.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1372https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1372Mon, 15 May 2017 15:01:03 +0100Collected Evidence: Collected Evidence: Soil: Plant hedgerowsOrganic matter (0 studies) Nutrients (0 studies) Soil organisms (0 studies) Soil erosion and aggregation (1 study): One replicated site comparison from the USA found similar particle sizes in soils with or without planted hedgerows. Greenhouse gases (0 studies)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1373https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1373Mon, 15 May 2017 15:03:05 +0100Collected Evidence: Collected Evidence: Soil: Restore habitat along watercoursesOrganic matter (1 study): One replicated site comparison from the USA found less carbon in soils at restored sites, compared to natural sites. Nutrients (1 study): One replicated site comparison from the USA found less nitrogen, phosphorus, and potassium in soils at restored sites, compared to natural sites. Soil organisms (1 study): One controlled study from the USA found different nematode communities in restored and unrestored areas. Soil erosion and aggregation (0 studies) Greenhouse gases (0 studies) Implementation options (1 study): One replicated site comparison from the USA found less carbon, nitrogen, and phosphorous in soils at older restored sites compared to younger restored sites.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1374https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1374Mon, 15 May 2017 15:07:41 +0100Collected Evidence: Collected Evidence: Soil: Exclude grazersOrganic matter (1 study): One replicated site comparison in shrublands in Spain found less carbon in soils at ungrazed sites, compared to cow-and-sheep-grazed sites. Nutrients (3 studies): Three replicated studies (one controlled, two site comparisons) from the USA and Spain found less nitrogen in soils in ungrazed areas, compared to sheep- or cattle-grazed areas, in some or all comparisons. One of these studies found more phosphorus in soils at ungrazed sites, compared to grazed sites. Soil organisms (1 study): One controlled study on a streambank in the USA found more nematodes and more diverse nematode communities in an area with goats and sheep excluded. Soil erosion and aggregation (0 studies) Greenhouse gases (3 studies): One replicated site comparison in shrublands in Spain found more carbon dioxide in soils (soil respiration) in ungrazed plots, compared to sheep- or cattle-grazed plots. One replicated, randomized, controlled study in grassland in the USA found similar amounts of carbon dioxide in soils (soil respiration) in ungrazed and cattle-grazed sites. One replicated, randomized, controlled study in wet grasslands in the USA found less methane in soils in ungrazed plots, compared to cattle-grazed plots. Implementation options (1 study): One replicated site comparison in shrubland in Spain found less carbon and nitrogen in untilled soils that were grazed, compared to ungrazed, but found no differences in tilled soils that were grazed or ungrazed.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1375https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1375Mon, 15 May 2017 15:11:34 +0100Collected Evidence: Collected Evidence: Soil: Use fewer grazersOrganic matter (0 studies) Nutrients (2 studies): One controlled study in wood pasture in Chile found more nitrogen and phosphorus in paddocks grazed at lower intensities, in some comparisons. One replicated, randomized, controlled study in grasslands in the USA found no difference in nitrogen between areas with low or high levels of simulated grazing. Soil organisms (0 studies) Soil erosion and aggregation (0 studies) Greenhouse gases (1 study): One replicated, randomized, controlled study in grasslands in the USA found no differences in rates of soil respiration between areas with low or high levels of simulated grazing.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1376https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1376Mon, 15 May 2017 15:13:39 +0100Collected Evidence: Collected Evidence: Source spat and juveniles from areas or hatcheries not infested with diseases or non-native or problematic species We found no studies that evaluated the effects of sourcing spat and juveniles from areas or hatcheries not infested with diseases or non-native or problematic species on subtidal benthic invertebrate populations.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2159https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2159Tue, 22 Oct 2019 12:09:40 +0100Collected Evidence: Collected Evidence: Soak trees/shrubs before planting: freshwater wetlands One study evaluated the effects – on trees/shrubs typical of freshwater wetlands – of soaking them before planting. The study was in a greenhouse in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Biomass/plant (1 study): One replicated, randomized, controlled study in a greenhouse in the USA found that soaking black willow Salix nigra cuttings before planting had no significant effect on the above-ground biomass of surviving seedlings, over the 48 days after planting. OTHER Survival (1 study): One replicated, randomized, controlled study in a greenhouse in the USA found that the effect, on survival, of soaking black willow cuttings before planting depended on the water regime after planting. However, all cuttings soaked for 15 days before planting died within 42 days of planting. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3361https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3361Sun, 11 Apr 2021 17:33:34 +0100Collected Evidence: Collected Evidence: Soak trees/shrubs before planting: brackish/saline wetlandsWe found no studies that evaluated the effects – on trees/shrubs typical of brackish/saline wetlands – of soaking them before planting.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3362https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3362Sun, 11 Apr 2021 17:33:44 +0100Collected Evidence: Collected Evidence: Soak tree/shrub seeds before sowing: freshwater wetlandsWe found no studies that evaluated the effects – on trees/shrubs typical of freshwater wetlands – of soaking their seeds before sowing.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3365https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3365Sun, 11 Apr 2021 20:17:00 +0100Collected Evidence: Collected Evidence: Sow grass seeds Thirteen studies examined the effects of sowing grass seeds on grassland vegetation. Six studies were in North America, five studies were in Europe and one study was in each of Canada and South Africa. VEGETATION COMMUNITY (6 STUDIES) Community composition (2 studies): One of two paired studies (one of which was replicated, randomized and controlled) in Hungary and the UK found that, over time, plant communities in areas where grass seeds were sown and in areas where no seeds were sown became more similar to those of intact grasslands. The other study found that plant communities in sown areas were different from those of ancient grasslands or sites where natural regeneration was allowed. Overall richness/diversity (4 studies): Three of four studies (three of which were replicated and controlled, and one of which was a site comparison) in the UK, Hungary, Iceland and the USA found that sowing grass seeds did not change or reduced overall plant species richness. The other study found that species richness was lower than that found in nearby intact prairies. Native/non-target species richness/diversity (1 study): One replicated, controlled study in the USA found that sowing grass seeds did not alter the species richness of native plants. VEGETATION ABUNDANCE (10 STUDIES) Overall abundance (3 studies): Two of three studies (including two replicated, controlled studies and one site comparison) in the USA, Iceland and Norway found that sowing grass seeds increased vegetation cover. The other study found that in two of three years there was no difference in vegetation cover between areas where grass seeds were sown and those where no seeds were sown. Characteristic plant abundance (1 study): One replicated, randomized, paired, controlled study in Hungary found that sowing grass seeds reduced the abundance of grassland species. Sown/planted species abundance (1 study): One replicated, controlled study in South Africa found that sowing grass seeds increased the abundance of sown species. Grass abundance (4 studies): Three of four replicated studies (two of which were randomized, controlled studies and the other a site comparison) in the USA and Canada found that sowing grass seeds either reduced native grass cover or did not alter native grass density. The other study found that after two years grass cover was higher in areas where grass seeds were sown than in areas were no seeds were sown, but after seven years there was no longer a difference between areas. Forb abundance (2 studies): One of two replicated studies (one randomized, controlled study and one site comparison) in the USA and Canada found that sowing grass seeds reduced the abundance of native forb species. The other study found no change in the density of native forb species. Tree/shrub abundance (2 studies): Two replicated studies (one randomized, controlled study and one site comparison) in the USA and Canada found that sowing grass seeds reduced the abundance of shrub species. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that sowing grass seeds did not alter the cover of native plant species. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3397https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3397Fri, 25 Jun 2021 13:05:51 +0100Collected Evidence: Collected Evidence: Sow grassland forb species One study examined the effects of sowing grassland forb species on grassland vegetation. The study was in Belgium. VEGETATION COMMUNITY (0 STUDIES) VEGETATION ABUNDANCE (0 STUDIES) VEGETATION STRUCTURE (0 STUDIES) OTHER (1 STUDY) Germination/Emergence (1 study): One replicated, controlled study in Belgium found that sowing seeds of grassland forb species did not increase the number of seedlings for three forb species. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3398https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3398Fri, 25 Jun 2021 13:53:08 +0100Collected Evidence: Collected Evidence: Sow grassland seeds from a local source Five studies examined the effects of sowing grassland seeds from a local source on grassland vegetation. Two studies were in Germany, two were in the USA and one was in Italy. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (1 study): One replicated, controlled study in Italy found that sowing grassland seeds from a local source increased plant species richness compared to sowing a commercial seed mix. Characteristic plant richness/diversity (1 study): One replicated, controlled study in Germany found that sowing grassland seeds from a local source, along with increasing the number of species in a seed mix, led to an increase in the species richness of target plants. VEGETATION ABUNDANCE (3 STUDIES) Overall abundance (2 studies): One of two replicated studies (including one site comparison and one controlled study) in the USA and Germany found that after sowing grassland seeds from a local source vegetation cover increased over time compared to areas sown with non-native seeds, but the density of individual plants declined. The other study found that vegetation cover did not differ to that in areas sown with commercial grass seed. Characteristic plant abundance (2 studies): One replicated, controlled study in Germany found that sowing grassland seeds from a local source, along with increasing the number of species in a seed mix, led to an increase in the cover of target plant species. One replicated, randomized, paired, controlled study in Germany found that sowing grassland seeds from a local source increased the abundance of one of four characteristic plant species that were sown. VEGETATION STRUCTURE (2 STUDIES) Height (2 studies): Two replicated studies (including one controlled and one site comparison study) in the USA and Italy found that sowing grassland seeds from a local source did not alter vegetation height compared to sowing non-native grass seeds or a commercial seed mix. OTHER (1 STUDY) Survival (1 study): One replicated, randomized, controlled experiment in the USA found that sowing Sandberg bluegrass seeds from a local source did not change the survival of sown plants compared to sowing non-local varieties. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3400https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3400Fri, 25 Jun 2021 14:08:23 +0100Collected Evidence: Collected Evidence: Sow native grass and forbs Fifty studies examined the effects of sowing native grass and forb seeds on grassland vegetation. Thirty-six studies were in Europe, twelve studies were in North America and one study was in New Zealand. One review included studies from Europe, North America and Africa. VEGETATION COMMUNITY (42 STUDIES) Community composition (11 studies): Five of 11 studies (10 of which were replicated and/or controlled, and three of which were site comparisons) in the UK, the Czech Republic, Norway and Germany found that sowing native grass and forb seeds increased the similarity of plant community composition to that of target communities. Three studies found no increase in community similarity to target communities. Two studies found that over time communities became more similar to those of intact grasslands. One study found that over time areas sown with native grass and forb seeds became more similar to areas that were not sown with seeds. Overall richness/diversity (28 studies): Sixteen of 28 studies (24 of which were controlled and four of which were site comparisons) in Europe, North America and New Zealand found that sowing native grass and forb seeds increased overall plant species richness. Seven studies found that there was no change in plant species richness or mixed effects on plant species richness and plant diversity. Three studies found that sowing native grass and forb seeds increased plant species richness during the first year, but after 3–13 years, species richness did not differ between sown and unsown areas or was lower in sown areas. One study found that after one year, sowing did not alter plant species richness but after eight years, species richness was higher than in unsown areas. Three studies found that species richness was lower in sown areas than in nearby intact grasslands. Characteristic plant richness/diversity (9 studies): Six of nine studies (eight of which were replicated and/or controlled, and two of which were site comparisons) in Europe found that sowing native grass and forb seeds increased the species richness of characteristic grassland plants. Two studies found no change in the species richness of characteristic grassland plants. One study found that sowing native grass and forb seeds increased the species richness of target forbs but not target grasses. Sown/planted species richness/diversity (3 studies): Three replicated, paired, controlled studies in the UK and the Czech Republic found that sowing native grass and forb seeds increased sown species richness. Grass richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that sowing native grass and forb seeds increased grass species richness in 54% of cases. Forb richness/diversity (1 study): One replicated, randomized, paired, controlled study in the UK found that sowing native grass and forb seeds increased forb species richness in 71% of cases. Native/non-target richness/diversity (1 study): One replicated, controlled study in the USA found that sowing native grass and forb seeds increased the species richness of native plants. VEGETATION ABUNDANCE (24 STUDIES) Overall abundance (8 studies): Three of eight replicated, controlled studies (four of which were randomized and paired) in Europe and North America found that sowing native grass and forb seeds increased overall vegetation cover, biomass or density. One study found that sowing native grass and forb seeds increased plant species richness during the first 2–7 years, but after eight years, species richness did not differ between sown and unsown areas. Four studies found that there was no change in overall vegetation abundance in all or most cases. Characteristic plant abundance (5 studies): Three of five replicated studies (four of which were controlled, and one of which was a site comparison) in Europe found that sowing native grass and forb seeds did not alter the cover of characteristic grassland species. The other two studies found an increase in the cover of characteristic or target grassland species. Sown/planted species abundance (6 studies): Five of six studies (four of which were replicated and controlled, and two of which were reviews) in Europe, North America, Africa and New Zealand found that sowing native grass and forb seeds increased the abundance of sown species in all or most cases. The other study found mixed effects on sown species abundance. Grass abundance (3 studies): Two of three replicated, randomized, controlled studies (two of which were paired) in the Czech Republic and the USA found that sowing native grass and forb seeds increased the cover of grass species. The other study found no change in the cover of grass species. Forb abundance (4 studies): Three of four replicated, randomized, controlled studies (three of which were paired) in the Czech Republic and the USA found that sowing native grass and forb seeds increased the cover or density of forb species. The other study found that one year after sowing, the cover of forb species increased, but after 10 years it did not differ between sown and unsown areas. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that sowing native grass and forb seeds increased the cover of native plant species. Individual plant species abundance (1 study): One replicated, randomized, paired, controlled study in the UK found that sowing native grass and forb seeds did not alter yellow rattle abundance. VEGETATION STRUCTURE (0 STUDIES) OTHER (2 STUDIES) Germination/Emergence (2 studies): One of two replicated, controlled studies (one of which was paired) in the USA and Germany found that sowing native grass and forb seeds increased the number of seedlings that emerged. The other study found no change in seedling number. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3432https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3432Mon, 28 Jun 2021 13:42:06 +0100
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What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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