春の日本の水田

片山直樹氏らの日本での研究によると、有機稲作は従来の農業よりも多くの植物、クモ、トンボ、カエル、水鳥を支えている。 A version of this post in English is available here. 20世紀半ば以降の農業の集約化と、より近年の耕作放棄は、農地の生物多様性に対する大きな脅威となっている。有機農法と低投入型農法(化学合成農薬および肥料の削減)は、農地の生物多様性を、進行中の生息地の損失と劣化から守る手段として期待されている。それにもかかわらず、有機農法や低投入型農法が生物多様性にもたらす利益についての知見は、主要な米の生産地であるアジアでは非常に少ない。 著者らの研究では、有機農法や低投入型農法で増える可能性のある様々な生物群(植物、クモ、トンボ、カエル、魚、および鳥)を、有機農法または低投入農法の水田で調査し、近隣の慣行農法の水田と比較した。1000以上の日本の圃場で現地調査を行った。日本では、主に地球温暖化防止や生物多様性保全のために、有機農法や低投入型農法を実施している農家に対して、国や自治体が支援を行っている(0.1 ha当たり最大8,000円=2019年5月21日時点で約72.6 USDまたは65.1 EURに相当)。 著者らは、有機農法の水田において、多くの生物群(在来およびレッドリスト植物、アシナガグモ属、アカネ属、およびトノサマガエル属)の種数・個体数が最も多くなることを実証した。水鳥の種数と個体数は、地域内の有機農法の実施面積に比例して増加し、これは広範囲で食物量を高めることの重要性を示唆した。また低投入型農法の水田は、慣行農法の水田よりも植物の種数とアシナガグモ属・アカネ属の個体数が多かった。さらに著者らは、農業者へのインタビューを通じて収集した農地管理に関するデータを用いて、化学合成農薬の低減や回避だけでなく、輪作の非実施、畦畔植生の維持および空間的にまとまった有機農業の実施によって、生物多用性に配慮した稲作が可能になることを示した。 これらの結果から、慣行農法と比較して、有機および低投入型稲作が農地の生物多様性が豊かであることが明らかになった。これにより、日本で実施されている農業環境政策(有機・特別栽培等に対する交付金制度)の効果について、科学的な評価基盤を提供することができた。さらに、輪作を回避すること、畦畔植生を適当な高さに維持すること、および有機栽培を行う水田を空間的にまとめることも、特定の分類群の保全に有効であることがわかり、こうした取組の推進が望まれる。 全文を参照, 有機農法およびそれに関連する管理手法が複数の生物群に利益をもたらす:水田景観における大規模な野外調査, in Journal of Applied Ecology. Continue reading 春の日本の水田

On the benefits of organic farming: Japanese rice fields in spring

Based on their research in Japan, Naoki Katayama and colleagues highlight how organic rice farming supports more plants, spiders, dragonflies, frogs and waterbirds than conventional farming. A version of this post in Japanese is available here. The intensification of agriculture since the mid-20th century, and the more recent abandonment of farmlands, have presented major threats to farmland biodiversity. Organic farming and less strict low-input farming … Continue reading On the benefits of organic farming: Japanese rice fields in spring

Editor’s Choice 56:7: Can agri-environment be successful in a pesticide world?

Executive Editor, Marc Cadotte, provides an insight into the important research of Humann-Guilleminot et al. Their recent article, A nation‐wide survey of neonicotinoid insecticides in agricultural land with implications for agri‐environment schemes, is our July Editor’s Choice. In response to general concerns about the impacts of agricultural activities on native biodiversity and ecosystem health, European jurisdictions have implemented agri-environment schemes that regulate and mitigate agricultural … Continue reading Editor’s Choice 56:7: Can agri-environment be successful in a pesticide world?

Parches boscosos en paisajes agrícolas: la estrategia para conservar las aves Neotropicales

An English version of this post is also available here. Tras investigar la biodiversidad en zonas agrícolas y ganaderas por varios años, se ha encontrado que las fincas, haciendas y jardines tienen mucho potencial para conservar la biodiversidad. Sin embargo, dichas áreas no son reemplazos de las áreas protegidas ya que hay algunas especies que solamente habitan en áreas protegidas. Un nuevo artículo de investigación … Continue reading Parches boscosos en paisajes agrícolas: la estrategia para conservar las aves Neotropicales

Conservation grazing on saltmarsh: are agri-environment schemes helping?

Following a recently published Research Article, Jennifer Smart explores this question and considers ways we can continue to work with the farming community to achieve conservation goals. Jennifer worked on this post with the British Ecological Society Policy team. In contemporary landscapes, grazing by domesticated cattle and sheep has become an increasingly important aspect of grassland management. This is largely because natural processes such as … Continue reading Conservation grazing on saltmarsh: are agri-environment schemes helping?

On the horizon: omega-3 fatty acids in oil crops – saving fish or threatening insects?

An emerging genetic technology that makes oilseed crops produce omega-3 fatty acids promises health and sustainability benefits, but there’s a potential adverse impact on insects that hardly anyone is talking about. Lynn Dicks and Xavier Le Roux round off our ‘On the horizon’ series. Polyunsaturated, long chain omega-3 fatty acids are the reason why healthy diet recommendations usually include seafood and oily fish like salmon, … Continue reading On the horizon: omega-3 fatty acids in oil crops – saving fish or threatening insects?

Sustainable intensification: our quest for the ‘holy grail’

Is it possible to meet food demands and increase production without the damaging costs to the environment? Patrick White et al. tackle this challenge in their recently published research in the journal. As the world population grows, our finite land is put under increasing pressure to meet food demands. Historically we have increased agricultural yields by increasing the intensity of agricultural practices – for example … Continue reading Sustainable intensification: our quest for the ‘holy grail’

Editor’s Choice 56:4 – A worm in the apple

Issue 56:4’s Editor’s Choice, Management trade-offs on ecosystem services in apple orchards across Europe: Direct and indirect effects of organic production highlights the need for more environmentally friendly pest control approaches in order to keep up with increasing production demands and avoid damage to pollination services. Associate Editor, Juan Corley, comments on the article. Strategy to minimize the negative effects of pests and weeds is … Continue reading Editor’s Choice 56:4 – A worm in the apple

Do wildlife-friendly farming subsidy schemes deliver their expected benefits?

Recently Michael MacDonald examined the impact agri-environmental schemes have had in the UK and, in particular, Wales. Now Associate Editor Peter Manning highlights the need to focus on evidence of these schemes’ effects when considering agricultural policy reform. There is now overwhelming evidence that agricultural intensification has proven disastrous for wildlife, and that policies encouraging intensification are a key driver in this process. In Europe … Continue reading Do wildlife-friendly farming subsidy schemes deliver their expected benefits?

U.S. policy-based management improves grassland bird nest survival – although finer-scale habitat has superior predictive ability

In a recent study, Justin Shew and colleagues found nest survival improved with policy-based management and establishing native grasses but conclude finer-scale details often have superior predictive ability from a multi-scale perspective. Read more about their findings here. A video summary of their work is also available. Grassland and farmland bird populations have been declining around the world and these declines are primarily attributed to … Continue reading U.S. policy-based management improves grassland bird nest survival – although finer-scale habitat has superior predictive ability